<script type="importmap">
  {
    "imports": {
      "vue": "https://unpkg.com/vue@3/dist/vue.esm-browser.js"
    }
  }
</script>

<div id="app">{{ message }}</div>

<script type="module">
    import { createApp, ref } from 'vue'

    createApp({
        setup() {
            const message = ref('Hello Vue!')
            return {
                message
            }
        }
    }).mount('#app')
</script>